Benjamin Markovits is an intriguing, sophisticated and accomplished writer. He is one of those who does not need to announce his mastery with an overly worked plot or exaggeration of speech or style; he has no need for grandiosity of theme. For although his new novel has all of the features of period costume drama inserted within a contemporary story, marked by quite complex themes of selfhood and identity, it nevertheless unfolds with a quietness and self-effacement that is the mark of true confidence in a storyteller.

Imposture tells a story within a story. It opens with Markovits himself relating the tale of a fellow teacher and closet writer who's clearly had some kind of reckless past, but is now living on as the empty vessel of its memories. All that's left of this man, Peter Pattieson (a man with a name that's been filched from another story), is a novel that he gave Markovits to publish after his death and that follows here as Imposture

Markovits sets out his stall right at the beginning then, alerting us from the outset that Imposture is, in itself, a play on notions of truth and fiction, the real and the pretend: 'Peter told the story,' he writes, 'of Hunt and Shelley's conversation about The Fall of Hyperion. Hunt had wondered how a little cockney apothecary who didn't speak a word of ancient Greek could make an epic of their mythology. I can still hear Peter mumbling the famous reply - through the soft mass of his beard, which was both the emblem and the instrument of his general reluctance to expose his face to the world. "And Shelley, whom envy never touched," Peter had said, "gave as reason that Keats was a Greek."' So you see? 'Imposture' though this book may be, it also has the ring of truth.

So the tale unfolds. A young man, Polidori, is hired to be Byron's doctor, not so much on the strength of his medical skills (Polidori's patients, we are told, all died under his knife), but because he looks like him. This is against his father's wishes, who senses nothing good will come of the association. Sure enough, as time goes on, the young doctor comes to be eviscerated, somehow, by Byron's presence. The joy he felt on seeing how similar they appeared has become a curse and he is left by the end of the book with a self that is good for nothing more than being able to pretend that he is the famous poet.

All this is effected in Markovits's signature style: a kind of literature that writes to the margins. He is not interested in telling a concrete, point-to-point narrative that is laden with facts; rather, he leads us to the edges - of consciousness, emotional truth - by way of an allusive and richly suggestive prose. Byron's presence is at the heart of this story, but there is also a Byron-shaped space where the heart should be. Markovits always lets us have a satisfying portion of detail and fineness of psychological and emotional information, but never lets this serving become the central dish. He leaves us wanting, in the most delicious way, more.

The other feature of this writer's work is a sense of the world. Not since Fitzgerald, to my mind, has there been a prose stylist who is so in love with things, the stuff and sensuality of privilege. Markovits renders, like Fitzgerald, the bright glitter that is cast by money across the surface of the world. And, like Fitzgerald, he also shows exactly the dullness, the grey-cuffed shame of not having money's careless sense of leisured ease. Markovits's last novel, Either Side of Winter, caught this theme in the setting of New York City, showing up contrasting worlds of easy entitlement and plain hard work in a range of interlocking stories.

In Imposture, we're in 19th-century London yet the atmosphere is the same. What does it feel like, Markovits seems to be asking in both these books, if you want certain things very badly and you don't have them? To read Imposture is to feel, along with the characters, exactly what it's like. One of the great tricks of this novel is that our reading of it becomes somehow a cloak that we ourselves wear.

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